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Weighted-Average Assumptions used to Determine Benefit Obligations and Net Periodic Postretirement Cost (Detail) - Postretirement Benefits | 12 Months Ended
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May 31, 2018 | May 31, 2017 | May 31, 2016
U.S. Plans |  |  |
Health Care Cost Trend Rates Assumptions [Line Items] |  |  |
Year-End Benefit Obligations, Discount rate | 4.03% | 3.61% |
Year-End Benefit Obligations, Current healthcare cost trend rate | 7.86% | 14.75% |
Year-End Benefit Obligations, Ultimate healthcare cost trend rate | 4.36% | 4.36% |
Year-End Benefit Obligation, Year ultimate healthcare cost trend rate will be realized | 2037 | 2037 |
Net Periodic Postretirement Cost, Discount rate | 3.61% | 3.76% | 3.95%
Net Periodic Postretirement Cost, Healthcare cost trend rate | 14.75% | 10.37% | 11.34%
Net Periodic Postretirement Cost, Ultimate healthcare cost trend rate | 4.36% | 4.36% | 4.50%
Net Periodic Postretirement Cost, Year ultimate healthcare cost trend rate will be realized | 2037 | 2037 | 2029
Non-U.S. Plans |  |  |
Health Care Cost Trend Rates Assumptions [Line Items] |  |  |
Year-End Benefit Obligations, Discount rate | 3.70% | 3.61% |
Year-End Benefit Obligations, Current healthcare cost trend rate | 6.02% | 5.85% |
Year-End Benefit Obligations, Ultimate healthcare cost trend rate | 4.20% | 4.20% |
Year-End Benefit Obligation, Year ultimate healthcare cost trend rate will be realized | 2032 | 2030 |
Net Periodic Postretirement Cost, Discount rate | 3.61% | 3.92% | 4.00%
Net Periodic Postretirement Cost, Healthcare cost trend rate | 5.85% | 5.98% | 6.06%
Net Periodic Postretirement Cost, Ultimate healthcare cost trend rate | 4.20% | 4.20% | 4.20%
Net Periodic Postretirement Cost, Year ultimate healthcare cost trend rate will be realized | 2030 | 2030 | 2030

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- Definition Defined benefit plan year ultimate healthcare realized cost trend rate. + References No definition available. + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 + Details
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